On Wed, Nov 25, 2015 at 02:29:56PM -0600, Rob Herring wrote: > On Wed, Nov 25, 2015 at 02:25:04PM -0500, Damien Riegel wrote: > > This watchdog is instantiated in a FPGA that is memory mapped. It is > > made of only one register, called the feed register. Writing to this > > register will re-arm the watchdog for a given time (and enable it if it > > was disable). It can be disabled by writing a special value into it. > > > > It is part of a syscon block, and the watchdog register offset in this > > block varies from board to board. This offset is passed in the syscon > > property after the phandle to the syscon node. > > > > Signed-off-by: Damien Riegel <damien.riegel@xxxxxxxxxxxxxxxxxxxx> > > Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> > > --- > > .../devicetree/bindings/watchdog/ts4800-wdt.txt | 25 +++ > > drivers/watchdog/Kconfig | 10 + > > drivers/watchdog/Makefile | 1 + > > drivers/watchdog/ts4800_wdt.c | 215 +++++++++++++++++++++ > > 4 files changed, 251 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > > create mode 100644 drivers/watchdog/ts4800_wdt.c > > > > diff --git a/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt b/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > > new file mode 100644 > > index 0000000..388c60f > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > > @@ -0,0 +1,25 @@ > > +Technologic Systems Watchdog > > + > > +Required properties: > > +- compatible: must be "technologic,ts4800-wdt" > > +- syscon: phandle / integer array that points to the syscon node which > > + describes the FPGA's syscon registers. > > + - phandle to FPGA's syscon > > + - offset to the watchdog register > > + > > +Optional property: > > +- timeout-sec: contains the watchdog timeout in seconds. > > + > > +Example: > > + > > +syscon: syscon@b0010000 { > > + compatible = "syscon", "simple-mfd"; > > + reg = <0xb0010000 0x3d>; > > + bus-width = <16>; > > + > > + wdt@e { > > + compatible = "technologic,ts4800-wdt"; > > + syscon = <&syscon 0xe>; > > If this is single register only for the watchdog, why do you need > syscon? You can just use reg. Because this is a single 16-bit register dedicated to the watchdog in a 60-register syscon. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html